A method is known of preparing hot-rolled semifinished steel stock for cold rolling, including its preliminary cold rolling in the rolls of a temper mill having a preset hardness and surface roughness, to a preset reduction in the range of 2 to 4% depending on the planned tonnage of the strip, and its subsequent pickling (RU 2183516, pub. Jun. 20, 2002).
A method is known of preparing hot-rolled semifinished steel stock for cold rolling, including preliminary cold rolling in the rolls of a temper mill with regulated surface roughness parameters of the barrel of these rolls and density of the peaks of the contour line with relative reduction of 2-8%, increasing with increase in the reeling temperature of the hot-rolled strip into coils, and subsequent pickling (RU 2492006, pub. Jul. 24, 2012).
The common disadvantage of these known methods is that their preliminary cold rolling of the semifinished stock does not achieve sufficient mechanical breakdown of the scale and complete removal thereof from the surface of the semifinished rolled stock, necessitating subsequent pickling of the semifinished stock.
The closest analog to the present subject matter is a method for the preparation of hot-rolled semifinished steel stock for cold rolling that includes its preliminary cold rolling in the rolls of a temper mill with a reduction of 3-8% and subsequent pickling (see the P. Polukhin et al. book, Rolling, Moscow, “Metallurgy”, 1982, pp. 485-487)—the prototype. The disadvantage of the prototype, as well as of the analogs, is the insufficient mechanical breakdown of the scale and incomplete removal thereof from the surface of the semifinished rolled stock during its preliminary cold rolling, which does not allow elimination of the subsequent pickling of the semifinished rolled stock.